The present invention relates to an overmolding method for making thermoplastics articles of manufacture, in particular for the perfumery and cosmetics fields.
A very important problem in the perfumery and cosmetics fields is that of making articles of manufacture, for example perfume vessel plugs, having a comparatively large thickness, by molding, usually by injecting molding suitable plastics materials.
At present, this problem is solved, for example, by the so-called overmolding process, including a first molding step, for example by an injection press, of the first plastics material, and a second molding step consisting of “overmolding” on the raw object or article of manufacture molded in the first step a second plastics material which may be identical to or different from the first plastics material.
The second overmolded plastics material may be different from the first plastics material, provided that they are compatible with one another.
The prior overmolding process allows to provide an aesthetically acceptable finished article of manufacture having a size and weight larger than those made by a so-called “single step” injection process.
The prior overmolding process, however, is affected by great drawbacks which do not allow to achieve a very accurate adjustment of the plastics material injection press.
A further drawback of the prior overmolding process or method is that, although it provides, as mentioned, an aesthetically acceptable article of manufacture, the aesthetic characteristics of the latter are due only to particular colors and thermoplastics material types, and accordingly would be susceptible to further improvements, for example by using or including other materials, such as metal and fabric materials, even of a precious type.